Method of regulation of ship-propulsion systems



June 7, 1932. G. MITZLAFF METHOD OF REGULATION OF SHIP PROPULSION SYSTEMS 'Filed Dec. 13, 1929 JOOOOOO zoooooo enone mzLAr-r, or mmvnzmn,

Patented June 7, 1932 BROWN BOVEBI & 01E, OF BADEN, SWITZERLAND PATENT OFFICE GERMANY, ASSIGNDE l0 AKTIENGESELLBCHAIT SWITZERLAND, A JOINT STOCK COMPANY 0] METHOD 0] REGULATION OF SHIP-PROPULSION SYSTEMS Application Med December 18, 1929,8eria1 No.

My invention relates to im rovements in methods of regulation of s ip- IOPlllSlOIl systems. In large modern ships w ich travel at a high speed it is no lon or possible to use a single Diesel engine for riving the propeller shaft, as it has hitherto been impossible for technical reasons to make Diesel engines of such power. Shi s of this kind are consequently fitted with several such engines which drive through suitable transmission members on to a single propeller shaft or on to several propeller shafts.

For transmittin the power electric machines have prove to be particularly suitable, continuous current'machines in Wardbeing frequently used,

Leonard connection and sometimes threehase synchronous generators with three-p ase synchronous inotors. Continuous current machines have the disadvantage that they are very heavy and that they require careful attention, owing to their delicate constructional parts, such as the commutator and brush apparatus. In addition to this, short-circuits are diflicult to deal with and with continuous current the employment of considerable voltages entails greater difliculties than is the case with three-phase systems. On the other hand three-phase synchronous machines which are preferred for these reasons have the disadvantage that they can only be started from the Diesel side, and that they mustbe synchroniz'ed before being connected up to the machines which are already running, which causes difiiculties due to the frequency vary ing with the speed of revolution of the propeller shaft and takes a certain amount oi time which makes the ship more diflicult to handle.

It has already been proposed to use, in stead of the synchronous machines of ordinary construction with definite poles, so called synchronized asynchronous machines which can be brought up to their full revolutions electrically as motors. These 1119; chines, after they have approximately reached the synchronous speed of revolution, are drawn into synchronism by switching in the continuous current excitation so that a revolution in the known elastic 113,915, and in Germany December 10, 1888.

synchronizing operation requiring a considerable amount of time is not required.

The present invention relates to the regulation of such a ships drive consisting of a number of groups, in which s nchronized asynchronous machines are use as generators. If a constant regulation of the speed of revolution were required this could onl be eii'ected in regulating the fuel supply 0 the separate iesel engines, as a regulation of the speed of revolution of the motors by means of a slip resistance could hardly he used for reasons of economy. lit is a peculiarity of ships drives theta speed regulation inrelatively large stages is usually quite suificient,

According to the invention, the regulation of the speed of revolution is effected by the operating" Diesel engine or engines losing set to the maximum fuel supply per stroke and the speed regulation hein putting Diesel engine units into and out of operation. The Diesel engine which is set to a constant fuel supply behaves as regards the dependence of the torque on the speed of manner re. practice as series-connection characteristic. With a constant resistance to motion through the water the speed is thus increased hy adding 2:. Diesel unit with constant fuel supply and decreased by the said unit being put out of operation without any other regulation being required. For reasons of reliability in operation automatic means must be provided which, on the high est admissible speed of revolution being exceeded, stops the constant fuel supply so that the set cannot race due to the enerator Being unexpectedly relieved of load? The invention also consists in using the known regulation of the speed of revolution hy changing the pole connections for obtaining lower speeds of revolution. According to invention, the change of pole (BMW-8" tions is efi'ected not in the usual manner at the motor, hut at the generators of the separate groups, and preferably only at some of the some. The robustness oi the driving system descrihed. shove enahles generators having changeable pole connections to be connected directly with generators having a fined numferred to in efiected solely by her of poles. In this case it will be of advantage to disconnect electrically the Diesel group with the generator changed over to the greater number of poles on a maximum speed of revolution being exceeded;

In the drawing a constructional example of the invention is illustrated as far as such a representation is diagrammatically possible.

1, 2, 3 and 4 show Diesel engines each with their fuel admission valves 5, 6, 7 and 8. They are coupled with flywheels 9, 10, 11 and 12 and with alternating 14, and 16, respectively. These machines are of the synchronized asynchronous type, two of them, 13 and 16, being provided with pole changing connections on their stator windings. The four generators feed into two main bus-bar systems 17 and 18, the generators 13 and 14 feeding the main bus system 17, and the generators 15 and 16 the bus system 18. The bus-bars can be paralleled by the I tie switch 19. The leads from the generators V of power units each inc an a 'tive prime. mover-st to the bus-bars pass over the main alternator switches 20, 21, 22 and 23 as well as the isolating-switches24, 25, 26 .and 27 The leads connecting the generators 13 and 16 pass over the pole-changing switches 28 and 29. -The generators are excited from the excitation bus systems 30 and 31 coupled by the tie switch 32. The excitation current passes over the field switches 33, 34, 35 and 36 and the field rheostats 37 38, 39 and 40 to the field winding of the generators 13, 14, 15 and 16. The ropellingmotors 47 and 48, which drive the 'p s propellers 51 and 52 through the couplings 49 and 50, are each connected to one of the bus-bar systems through the isolating switches 41 and 42, the reversing switches 43, and 44 and the star-delta switches 45 and 46. The right-hand propeller 52 is arranged at the starboard side; the left-hand one 51 at the port side. The drives on each side of the ship can, therefore, be operated inde en'dently of each other, by the opening 0 the tie switches 19 and 32.

I claim as my invention: 1. The method of speed regulation in a shiprepulsion system comprlsing a motor supp ed with operating power by a plurality udin a prime mover nerator driven therei comprising setting the operating units with the respective prime movers thereof fed constantly at substantially their maximum rated fuel supply, and putting the'units into and out of operation as speed of operation of the motor.

2. The method of speed regulation in a ship-propulsion system comprising a plurallty o power units supplying a motor and each including a prime mover and agenercurrent generators 13,

required to regulate the ply, putting the units into and out of operation as required for regulation of the speed of operation of the motor in the higher speed GEORG MITZLAFF.

y, said method igo ator driven thereby, said method comprising setting the operatm 'units' with the respecereof 'fe'd'constantly' at substantially their maximum rated fuel sup.- 

